As Wandering Nomad replied, it is to allow for expansion and contraction. Not only do the exterior temperatures vary significantly (for the above ground portions) but the internal temperatures do likewise as oil flow changes. There is a pretty ingenious design of sliders, anchors, bumpers, etc. to keep the pipeline aligned, yet allow it to move to adjust for changes in overall length. The area where the pipeline passes over the Denali Fault in Isabel Pass has even greater allowance for movement, with room to move back and forth across 20 feet or more. Can't seem to find any photos in my collection right now, although I know plenty have been taken, so next time I'm up that way I'll take some and post them.

Here are a couple of photos that give a little hint of what goes on. In this photo, on the south side of an overcrossing, the pipeline has slid to the right side of the supports.
You can see that the covers over the pipeline are almost touching the VSM's (Vertical Support Members) on the one side.

But on the north side of the crossing, the pipeline is more evenly centered on the supports -

You would be amazed how much a pipe will grow as it heats up in the sun during the day.

And it will damn sure contract at the temps that pipeline sees.

Lewis (EX-Piper)

Quote:

Originally Posted by Alcan Rider

As Wandering Nomad replied, it is to allow for expansion and contraction. Not only do the exterior temperatures vary significantly (for the above ground portions) but the internal temperatures do likewise as oil flow changes. There is a pretty ingenious design of sliders, anchors, bumpers, etc. to keep the pipeline aligned, yet allow it to move to adjust for changes in overall length. The area where the pipeline passes over the Denali Fault in Isabel Pass has even greater allowance for movement, with room to move back and forth across 20 feet or more. Can't seem to find any photos in my collection right now, although I know plenty have been taken, so next time I'm up that way I'll take some and post them.

Here are a couple of photos that give a little hint of what goes on. In this photo, on the south side of an overcrossing, the pipeline has slid to the right side of the supports.

You can see that the covers over the pipeline are almost touching the VSM's (Vertical Support Members) on the one side.

But on the north side of the crossing, the pipeline is more evenly centered on the supports -

Thanks fellas, I am from the hot north of Australia so didn't even begin to think of the extremes of temperature this area must face. Crikey what an engineering marvel and what an absolute hoot it must be to ride in this area.

__________________Yee Haa

...it's not the years in your life that count. It's the life in your years.

As promised, some photos of the sliders that support the pipeline over the Denali Fault. These are designed to allow the ground to shift up to ~30 feet sideways without overstressing the pipeline. While this is not on the Dalton Hwy, it is an important part of the pipeline that is the reason for the Dalton's existence.

Looking downstream, toward Valdez. The lane to the left of the photo is the gated access road used by security guards who constantly patrol the pipeline, and for maintenance crews.

A couple of photos showing detail of the supports. The main horizontal H-beams also rest on sliders embedded in the ground.
A fairly major earthquake that occurred along the Denali Fault on November 3, 2002 severely tested the design, and it did its job just as engineers had hoped it would.

And looking upstream, toward Prudhoe Bay.

To get back on track, a photo taken on Labor Day showing some fall colors along the South Fork Koyukuk valley.

Is that a wing i see before me n here was me fretting about the ride next june on my bmw gsa 1200
it would be good on the wee suzuki dr350 but that would make it a long haul from Frisco n back in 4 weeks
So looking forward !!!!!!!!!!

A few more from the Labor Day ride. Another shot of Beaver Slide from just below the Arctic Circle wayside, but this one has fall colors.

Just a couple miles south of "Oh Shit Corner", looking southwest.

From the top of Gobbler's Knob, looking out across the Jim River valley, with Pump Station 5 visible on its little hill.

If you happen to be on the Haul Road during hunting season, you may see a large number of vehicles parked in many of the available locations, such as this gravel area at Grayling Lake. There were two float planes on the lake as we went by, one preparing to take off, the other tied up along the north shore.

Between two of the Jim River bridges, fall colors border the highway and, combined with the mild weather, made the ride extremely enjoyable.

The MTF (Motorcycle Tourers Forum) has a "group" ride planned from Key West to Deadhorse (and back to Key West for the truly insane) for June 5th thru 18th. UCC/UCCC

HayDuchessLives and I will be taking a run up to Deadhorse over Memorial Day weekend again, and there are bound to be many more riders on that road this summer, regardless of conditions. If you want company on the ride, you can usually meet other riders going that way at either the UAF dorms or at Adventure Cycleworks.

The UCC/UCCC looks crazy. Have to give it to them that it would take determination to put that many miles in that short a time (if one's going for the record).

I'm thinking of starting this trip either in June or July (I have to be in CA for a wedding at the end of June), and it would be nice to meet other riders during this time. I'll check in here as well as the other resources to link up with other riders.

The UCC/UCCC looks crazy. Have to give it to them that it would take determination to put that many miles in that short a time (if one's going for the record).

I'm thinking of starting this trip either in June or July (I have to be in CA for a wedding at the end of June), and it would be nice to meet other riders during this time. I'll check in here as well as the other resources to link up with other riders.

I'm not going for the record. But I do intend to make this ride. It is one of the IBA rides I don't have in the book yet.
I tried it in '09 but my LT broke down in Miami. I took it home and grabbed the wing. It took five days steady riding to get to Fairbanks and thin I spent a week just riding around looking.

The MTF UCC will give yu a minimum of 10 days to get to Fairbanks and four days up the Dalton and back. I intend to sight see a bit on the way up and back.

I'm not going for the record. But I do intend to make this ride. It is one of the IBA rides I don't have in the book yet.
I tried it in '09 but my LT broke down in Miami. I took it home and grabbed the wing. It took five days steady riding to get to Fairbanks and thin I spent a week just riding around looking.

The MTF UCC will give yu a minimum of 10 days to get to Fairbanks and four days up the Dalton and back. I intend to sight see a bit on the way up and back.

Come join us. It is going to be fun.

You can do the Dalton in 48 hrs if you really pushed it and the weather played nicely. We made it up and back to Fairbanks in 3 days. On the way out it poured on us all the way outside Deadhorse until we got almost to the Yukon River Crossing. We still were able to ride the entire trip out in 14 hrs with a bout a 2 hours of taking breaks. Was a killer day but but we were psyched we did it!